Leroy Gordon Cooper, one of the nation's first astronauts who once set a space endurance record by traveling more than 3.3 million miles aboard Gemini 5 in 1965, died on Monday, NASA said. He was 77.
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In his post-NASA career, Cooper became known as an outspoken believer in UFOs and charged that the government was covering up its knowledge of extraterrestrial activity.

"I believe that these extraterrestrial vehicles and their crews are visiting this planet from other planets, which obviously are a little more technically advanced than we are here on Earth," he told a United Nations panel in 1985.
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He added, "For many years I have lived with a secret, in a secrecy imposed on all specialists and astronauts. I can now reveal that every day, in the USA, our radar instruments capture objects of form and composition unknown to us."